1. Field of the Invention
This invention relates to recreational vehicles, specifically to an improved level indicating device for motorhomes or like vehicles with four ground contact points.
2. Description of Prior Art
Leveling a heavy motorhome is a difficult task without the use of optional and very expensive hydraulic or electric levelers as explained by Pulsifier U.S. Pat. No. 4,974,801 Dec. 4, 1990. These levelers frequently run $3000.00 to $4500.00. Due to this additional expense most motorhome owners opt to carry wooden or plastic blocks and boards to place on the ground in ramplike fashion to the estimated height required for the individual wheels to bring the vehicle to a near level position. The vehicle is then driven up on the blocks, which usually requires several attempts at rearranging the height of the blocks before a satisfactory near level position can be obtained. This near level position is required for proper operation of recreational vehicle refrigerators, also stated by Pulsifer U.S. Pat. No. 4,974,801 and Marantz U.S. Pat. No. 5,136,784 Aug. 11, 1992. Severe damage to refrigerator units can occur if units are improperly leveled. Pulsifier's invention levels the appliance only and does not deal with leveling the entire vehicle which is important for the comfort of the occupants as well as the proper operation of doors, the drainage of sinks and tubs, to name a few. Marantz U.S. Pat. No. 5,136,784 differs due to the fact that it is electronic, does not indicate in inches the height to stack blocks for the individual wheels and is relatively expensive.
Most existing leveling devices are designed to level a vehicle with a two step operation, as with a camping trailer which has centrally located axle or axles and can simply be towed up on ramps or blocks to level horizontally. Being much lighter than motorhomes, trailers are sometimes raised with mechanical jacks to a horizontal position. With the horizontal leveling accomplished, which is step one, step two is simply a matter of raising or lowering the hitch end of the trailer unit until it is leveled longitudinally. Motorhome leveling is much different. With the axles located near the ends of the vehicle it can easily be seen that the same method does not work for leveling a motorhome. Recreational vehicle users frequent campgrounds and the like that are most often on uneven terrain. A motorhome on uneven terrain would be unlikely to have more than one wheel on the same elevation. To level the vehicle without the use of expensive jacks can only be accomplished by stacking blocks and boards as described above to the required height for the individual wheels and then driving the vehicle up on the blocks. Keeping the above in mind it can easily be seen why a leveling device that gives simultaneous readings for the four corners of a vehicle in inches is greatly needed by motorhome users.
Several patents have been issued for recreational vehicle leveling devices. For example, U.S. Pat. Nos. 4,542,592 to Hopkins (1985), 4,760,649 to Preston (1988), 4,567,666 to Neis (1986), 3,657,695 to Birmingham (1972), and 3,660,840 to Plofchan (1972). Of the aforementioned leveling devices none address the problem of giving the user a four point readout in inches, high or low, in order for a four wheeled vehicle to attain a level position in one simple maneuver. All leveling devices heretofore known suffer from a number of disadvantages:
(a) Leveling devices that simply give an indication that your vehicle is off true horizontally longitudinally and transversely are of little value when blocks must be placed at several points to a particular height in order to level a 10,000 to 20,000 lb. vehicle. PA1 (b) Leveling devices designed for camping trailers are not suitable for motorhome leveling due to the fact that trailers can be towed slowly onto a ramp for lateral leveling and then the tongue can be lowered or raised for longitudinal leveling. This can be in two separate steps with different requirements for the leveling device. They are not designed for four point leveling. PA1 (c) Electronic levels often require installation which is usually quite expensive and often require expensive maintenance. PA1 (d) A leveling device that indicates a particular corner of a motorhome is low is of little use to a user who then must estimate the number of inches of blocks to stack at possibly three points before driving his vehicle up on them for a level vehicle. PA1 (e) Mainly they do not provide measurements for leveling four wheels simultaneously. PA1 (a) To provide a reasonably priced mechanical leveling device that is simple to operate and does not require expensive installation. PA1 (b) To provide a leveling device that gives simultaneous readings for four corners of a vehicle in inches low and high as required for the proper leveling of a motorhome. PA1 (c) To provide the vehicle operator with adequate elevational information in inches so that numerous attempts are not required before a level condition can be met. PA1 (d) To provide RV owners/operators a means to level their vehicles in a much faster way than was previously possible with other methods. PA1 (e) To assist motorhome and other RV operators and owners in protecting their refrigerators and other appliances from expensive damage due to improperly leveled vehicles. PA1 (f) To make it possible for motorhome and other RV users to park in locations they previously would not attempt due to the problems of leveling a four wheeled vehicle. PA1 a base unit; PA1 a pivotal support attached to the base; PA1 an upper housing affixed to the pivotal support; PA1 a horizontal level indicating means affixed to the upper housing; and PA1 four mechanical measuring indicating means affixed to the upper housing having a ratio adjustment means, said measuring indicating means giving indication of elevational difference at four points relative to a true level surface, whereby vehicle attitude adjustment can be made based on the elevational differences noted on the measuring indicating means.